Abstract：The modulation strategy of three-level grid-connected inverter is very complexible, and it is hard to be implemented with DSP. A dual-reference waves based three-level SPWM method suitable for implementation by DSP is proposed, and then the dynamic mathematical model of the grid-connected inverter based on the aforementioned PWM method is derived. On the basis, aiming at the problem that conventional grid-connected deadbeat control is sensitive with the change of filtering inductor, an online inductor identification method adopting instantaneous current samples is proposed. The deadbeat current control is improved with the proposed method, thus the grid-connected current control performance is efficient. Corresponding experimental results verify the accuracy and feasibility of the proposed method.
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2012, Vol. 27 
